The present invention relates to medicine and more particularly to neurosurgery, and can be used in the operative treatment of patients with parasagittal meningiomas.
Parasagittal meninglomas (PSM) are a kind of meningioma whose initial growth point is, as a rule, a side wall of the upper sagittal sinus (USS), less frequently the tumor is anatomically connected with the falx cerebri. PSMs constitute about one half of all meningiomas. Usually PSM grows with the node outwards from the wall of the sinus, crushing the adjacent brain but not growing through it. Another direction of the PSM growth Is the USS lumen till the latter becomes completely obturated and the tumor extends to the opposite side.
Known in the art is a method for removing a parasagittal meningioma (see Irger I. M., “Neirokhirurgiya”, Moscow, 1972 (in Russian)). This method employs bi/monopolar electrocauterizing of the starting region of the tumor growth (matrix which is usually located on the side wall of the upper sagittal sinus).
However, this method leads to perforation of the side wall of the USS, to development of massive hemorrhage, and also to recurrent tumor.
A method for removing a parasagittal meningioma is also known (see Gabibov G. O., Ph.D. thesis “Clinical Picture, Diagnosis and Surgical Treatment of Parasagittal Meningiomas”, Moscow, 1967 (in Russian)), which comprises carrying out osteoplastic trepanation and opening of the dura mater in the projection of the tumor location.
This method is disadvantageous in that the tumor Is removed mechanically as large fragments or piece-wise, which may cause abundant hemorrhage.
USS ligation in the course of the operation (particularly In the middle and rear third thereof) often leads to serious complications (postoperative lethality with the tumor located in the middle third of the USS is 9.8%; with the tumor located in the rear third of the USS, 33.3%), and even to lethal outcomes (according to the data reported by different authors, the total postoperative lethality after the removal of PSM varies from 14 to 27%). USS ligation in the front third thereof is relatively safe. Here lethal outcomes are caused by venous hyperemia with subsequent development of venous infarctions, edema of the brain, dislocation and displacement of the truncus cerebri (so-called “wedging-in”).